Sound-purifying device



March 8 ,1927.

- 1,620,367 H. LION SOUND PURIFYING DEVICE 1 Filed April 18, 1925 ill/Trim I Jim/111mm Patented Mar. 8, 1927.

I v I 1 1,620,367 UNITEDSTATES PATENT OFFICE.

HENRY LION, or PARIS, FRANCE.

SOUND-PURIFYING DEVICE.

Application filed April 18, 1925, Serial No. 24,0 78, and in France April 28, 1924.

The apparatus for the propagation of sound which are currently employed, such as an acoustic funnel, vibrating box, vibrat-- mg conical piece and the like'transmit the vibrations by the perturbations in the volume of air which they-contain, but in virtueof the fact that they are likewise subject to vibration, the will prove a source of prejudicial parasitlc vibrations reproduced waves.

The said parasitic vibrations may be partially attenuated by the use of devices actingagainst the propagation of waves in the body of the reproducing element itself. But

even though it has been feasible to obviate the above-mentioned drawback, it is none the less true that the known emission devices will amplify Without any diminution the parasitic vibrations due to the scraping action of the gramophone disk or the phonograph cylinder, as well as the metallic vibrations occurring in the loud speaking apparatus employed for receiving purposes in radio tele hony. y

y invention has for its object an apparatus for the suitable filtering of the emitted sounds, while aifording the proper amplification of the normally emitted sounds, but eliminating'the parasitic sounds.

This result is obtained by disposing in the path of the sound waves one'or more vibrating filters consisting of series of diaphragms which are folded, embossed or corrugated,

and whereof the folds, embossed parts or corrugations are angularly spaced by a suitable amount from one diaphragm to the next. I

The'following description relative to the appended drawings which are given by way of example, clearly explains the manner in which the invention is carried intoeffect.

Fig. 1 is a sectional view of an embodiment of the invention I Fig. 2 is a corresponding perspective View, two consecutive diaphragms being shown in external view in the position which they. occupy in the apparatus. A

Fig. 3 is a detail View showing the superposed diaphragms on a larger scale and -according to two sections at right angles.

In the form of construction shown in Figs. 1 to 3, the apparatus which is adapted for'mounting upon an acoustic funnel'of circularcross SGCtlODCOIlSlStS of a drum which q is made of thin wood and has formed therein the lateral slots- I, said drum beentering into the ing fitted upon the edge of the acoustic fun- Iiel B G through the medium of a felt packmg member. Outwardlyof the said packing member is disposed a circular band F F Uponthe said band is-caused to I (Fig. 1). beer, at its edge, the first diaphragm of a series comprising a variable number of diaphragms according to the effect to be obtained. j

The said 'diaphragms a consist of strong paper which is folded in corrugated shape, with a depth of 5 millimeters.

posed diaphr'agms will offer a certain elasticity, and due to a slight pressure exercised upon the last diaphragm at G the whole device can besecurely held in place.

Fig. 2 is a perspective view of the device which is shown in section in Fig. 1; Fig. 3 is a full-size viewshowing the superposition of the diaphragms whose'directions of folding are orthogonal.

The substances formin the outer envelope may be of any suita le nature such as wood, metal, plastic substance or the like, provided the said envelope is light and ardly sonorous.

As to the nature of the substances constituting the said diaphragms, the latter must be 1i ht as well as strong, and must be readily shaped for instance by folding, embossing or the like. Suitable results are afforded by glazed paper, Bristol paper and chiefly by acetate of cellulose.

What I claim is:

1. A purifier of sounds, adapted to be juxtaposed or combined with an acoustic emit-- ter, comprising a box made of light material which is but little susceptible of vibration" As shown in Figs. 1, 2, 3, the said diaphragms are direction of the corrugations of the adjacent directions of the corrugations ofeach diadiaphragm. phragm making a certain angle with the 2. A purifier of sounds, adapted to be juxdirection of the corrugations of the adjacent taposed or combined with an acoustic emitdiaphragm, and means formaintaining the 5 ter, comprising a box made of light material said ,diaphragms within the said box. 15

which is but little susceptible of vibration In testimony that I claim the foregoing and having apertures formed in the lateral as my invention, I have signed my-name I faces of the box, a plurality of corrugated hereto.

diaphragms made of a light and strong sub- 10 stance and disposed Within the said box, the HENRY LION. 

